Let's talk muzzle velocity....

[JimmyHoffa]

I don't know if being in the mag warms them up that much.  When you wait between shots to you leave the bolt open after the shot, then chamber right before the next shot or chamber immediately and then wait before the next shot?

[Blacklab]

1/2 inch moa @ hundred yards is great. If your thinking of trying longer ranges say 500 +. Then you need to bring your sd down as close to 10 or lower consistently. Case prep and bullet seating is of great importance. Measure your chamber length. Some rifles like long jumps some like short. You want your ogive as close to the lans without touching.   

[high country]

I'd aneal the necks and play with depth.  The spread is the killer if you shoot much beyond 5ish hundred.

Reloder 26 will take you over the 3 grand mark.....it did for me. I was shoving 130's at 2900 and now 150 LRAB @3k on the nose with single digit spreads.

[bobcat]

I'm getting 3100 feet per second with 140 grain Bergers and RL26. My previous load with H4831 and the same bullet was 2,850 fps. Probably will never use anything but RL26 for my 270 Win.

[bearpaw]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

[high country]

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

The good news is you are on a node - but you knew that.  With that deviation in speed having little impact on accuracy you are in the sweet spot.   Watch temps. Are u sitting rounds out then putting in single just before shot?  Or are they warming in mag?  Loading to .1 grain accuracy?

I was placing 3 rounds in the mag.  Is it better to have them out or in?  I do load to +/- .1 grain, measuring every load with a lyman electric scale. 

I am going back up today and will shoot one round, let cool for 3-5 minutes, shoot another, etc....  Little more time between shots.  I was also going to buy a crimp die before I go back today.  I want to crip 5 rounds and see what happens. 

I've never crimped bullets either, I'm wondering if you found crimping to be more accurate?

I struggled to get a known good shooting rifle to shoot a nosler lrab. After speaking with nosler tech it's a pretty common problem for that bullet with slow powders to have inconsistent dwell time in the throat.....Sometimes it glides through, sometimes it hangs for a moment and then takes off again after the case pressure builds.

Their advice was either find ways to increase the time between ignition and the bullet contacting the leade......more depth, crimp, hotter primers or faster powders.

I found that I can get that bullet to shoot well by using a faster powder. .....but I also took a 3" load down to .6" by seating deep and crimping.

While 99% of the time it's unnecessary to crimp a rifle load, there are times that it helps tremendously.

[wsmnut]

If you are going to start crimping I'd back off the powder charge and work up again.
I don't really see the necessity for it myself.
Barrel temp is likely what is affecting your speed.  It's hard to be patient when you are out at the range.  Bring two rifles and alternate shooting them.  Keeps one cooling and you shooting!
I have two .270's.  One likes H4831, the other likes H4350.  Your rifle clearly likes what you are doing.  And H4350 is one of Hodgdon's extreme line which is noted to be less temperature sensitive.
     Try your speed test again by going out to the range with an already fouled barrel.
You might find things settle down a bit.

Good Luck!

[rudysts]

There are two methods that I do to bring down extreme velocity spreads.

1 Control of your neck tension, this can be done with a full length bushing die or neck bushing die.
http://www.accurateshooter.com/technical-articles/reloading/neck-tension-not-just-bushing-size/

2 Testing different primers. I have found in my non magnum rifles that CCI BR2 or the 200s gave me best results along with Federal gold medal match 210s with the magnums CCI 250

By using this method I have been able to reduce my ES down in to the low 20s and in to the teens and some times single digits.
I think the more important number is your SD (standard deviation) this should be single digit. but if you only shoot short range high ES won't matter they will still shoot tight but it will show up at longer ranges 300 plus yards.

I never saw the need to crimp a bullet on a bolt rifle, much better to use a bushing die http://www.whiddengunworks.com/standard-reloading-dies/  I think these are the best dies out there they also come with a shoulder bump gauge.

[high country]

The lrab/slow powder combination is one that requires some nontraditional techniques. If you don't believe me, call nosler tech support and ask for yourself.

[jrebel]

Kind of interesting changes from my last trip.  I loaded a few more rounds with my newly cleaned trimmed brass (I changed cleaning methods from media tumbling to stainless steel), as well I let the barrel cool a little more between shots and my s/d went from mid 20's to 15.  I currently have more loaded with different primers....Some magnum and others just different brands.....I will see if I get these numbers even tighter.  Next I will work with seating depth though I think I have already found that sweet spot.  Updates to follow. 

[Blacklab]

That's great 

[jrebel]

OK....a good update after some tinkering. 

I reloaded a few rounds using different primers.  I was using Winghester LR primers for the original load.  This last load I used Federal Magnum Rifle primers and hands down had the most consistant velocities. 

5 Shot group...waiting 5-6 minutes between shots. 

Min:         2686
Max:        2701
Average:  2693
ES:          15
SD:          5.6

One thing I did notice...the magnum primers are flattening out.  They are not cratering and are not to concerning, but definitely appears to be highter pressures in causing flatter primers....at least compared to the LR primers.  Didn't get any better velocities though so I can't imagine the pressures are that much higher.     Anyone have any imput? 

[bobcat]

I know velocity isn't everything but I wouldn't be happy getting less velocity with a 270 than you're getting with your 308. Yes your accuracy is good but why not have both? Like I said before I'm using Reloder 26 and getting 3100 fps with 140 grain Bergers. Most of the time it will put three shots almost in the same hole at 100 yards. For many years I had used H4831 with 140 or 150 grain bullets and always got between 2800 and 2900 fps.

[jrebel]

I know velocity isn't everything but I wouldn't be happy getting less velocity with a 270 than you're getting with your 308. Yes your accuracy is good but why not have both? Like I said before I'm using Reloder 26 and getting 3100 fps with 140 grain Bergers. Most of the time it will put three shots almost in the same hole at 100 yards. For many years I had used H4831 with 140 or 150 grain bullets and always got between 2800 and 2900 fps.

I'm not sure less velocity with one caliber or another is reason to get me worked up.  I like that both rifles are ballistically similar, it makes switching between the two very easy.  I also don't shoot these guns beyond 400 yards so the difference in a couple hundred feet per second is negligable. 
I have tried to push the limits of speed with this set up and it just doesn't like it.  I have not tried other powders because I have so much H4350 and it has worked for so long.  I guess in short, It works...so haven't considered changing bullets or powders.  This combo has killed many of animal with excellent results. 

Maybe I need to buy another .270 so I can work up a speedy load.....don't give me any excused to own another rifle.   

[bobcat]

Well, there's something to be said for lower recoil loads too, I'd like your load for that reason, also the fact that it's easier on your barrel.

I'm loading my 338 Win Mag to only around 2,750 with 210 grain Partitions, and some may think that's too mild.

But that's the nice thing about handloading. You can tailor your loads to exactly what you want.